with it having a time limit and low cost it makes me think too much of dimensional shield, and even then itd be weaker (even though it costs less and lasts longer). I mean can air have some more unique cards? (Shockwave weaker version of lightning) (Fog weaker version of Dusk) (Wings weaker version of Dim shield)
I would rather see it with an upkeep cost and a higher cost than a limited amount of effectiveness, or maybe even each turn costs 1 more for upkeep
It also costs half as much to play and lasts 2 more turns, but yeah I see your point.
EDIT: Maybe it should be more similar to Flooding/Inundation. Make it a normal permanent instead of shield/permanent, change up it's ability a little, and give it an upkeep cost of 3. Like Miracle & Fractal are quanta wipe cards (with more on the way?), maybe Flooding and Wings could start their own cycle of cards with 3 quanta upkeep costs.
IDEA: Each card in this cycle should do something that alters the play area, including graphically, like how Flooding adds the water graphic.
MY SUGGESTION: I'm not sure about Wings, but I'd like to see a Time card that costs 2 Time to play with 3 Time upkeep that makes each player's deck glow yellow around its borders. "Each player draws an additional card every turn." (This effect doesn't stack with multiple copies in play.